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000
FXUS63 KAPX 221926
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
326 PM EDT Thu Jul 22 2021

.NEAR TERM...(Through Tonight)
Issued at 247 PM EDT Thu Jul 22 2021

...Light Rain Possible, Thunder in the Morning?...

High Impact Weather Potential...Minimal.

Pattern Synopsis/Forecast...A warm front, associated with low
pressure in North Dakota, and extends into W Illinois, is
producing clouds and sprinkles over the forecast area this
afternoon. As this system, as well as the 500 mb ridge pattern
moves east, the chances for more significant precipitation will
increase overnight.

Primary Forecast Concerns...with the cloud cover, the primary
concern is the thunder potential overnight as the differential
advection and a weak 500 mb trough, and the warm front couple to
produce better chances for thunder. Not expecting severe as the
CAPE and shear are pretty limited, but a few rumbles in the SW
part of the forecast area by 12z aren`t out of the question.

&&

.SHORT TERM...(Friday through Sunday)
Issued at 247 PM EDT Thu Jul 22 2021

...Increasing Chances for Showers and Storms...

High impact weather: Locally heavy rainfall possible Friday night
and Saturday morning.

Models continue to struggle over the timing and extent of possible
convection over the next couple of days. Models do agree that
moisture steadily increases Friday into Saturday. Meanwhile, a
nearly stationary front located off to our south and west will begin
to move slowly toward the area. Although this front will initially
be south of the region Friday, it is expected to become the focus of
some shower activity. In addition, warm air advection is on the
increase with surface dewpoints rising through the 60s Friday and
perhaps touching the low 70s Saturday. Precipitable water values
increase to between an inch and 1.5 inches Friday and between an
impressive 2 and 2.25 inches Saturday. So there could be some
instability daytime heating driven showers and storms Friday (0-6 km
mixed layer cape of several hundred J/kg) possibly aided by some
lake breezes. A short wave moving through the flow in combination
with robust amounts of moisture will bring better chances for
showers and storms as well as lead to a heavy rain threat later
Friday night into the day Saturday. Some spots could see upwards of
an inch or more. The severe potential is a bit uncertain. There is
decent vertical and speed wind shear (0-6 km bulk shear 30 to 40
knots) but the amount of instability is more uncertain. More stable
conditions return for Saturday night into Sunday.

Temperatures will be warm through the period with highs in the low
and mid 80s with lows in the muggy 60s to near 70 Friday night and
the low and mid 60s Saturday night.

&&

.LONG TERM...(Sunday night through Thursday)
Issued at 247 PM EDT Thu Jul 22 2021

...Very Warm; Uneventful Weather to start the Week...

High impact weather potential: None is expected.

A building upper level ridge across the western states will lead to
a nearly zonal flow aloft across the Great Lakes leading to very
warm temperatures. A short wave moving through the flow may bring a
few showers toward mid week. Temperatures look like they will be at
least a few degrees above normal through the period.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 247 PM EDT Thu Jul 22 2021

The high CIGs will begin to lower over night as the warm front and
weak 500 mb trough moves over the Upper Great Lakes. However, the
Most of the CIGs upstream are VFR with some MVFR mixed in, so will
expect that the CIGs will remain VFR with some temporary MVFR CIGs
overnight. The potential for rain, and thunderstorms will increase
as we get into the afternoon, but especially after the 18z/Fri
ending of the current TAF period. Occasional MVFR CIGs are
expected for the morning as well.

&&

.MARINE...
Issued at 247 PM EDT Thu Jul 22 2021

Tonight through Saturday...High pressure will slowly slide off
overnight, allowing winds to increase over the region on Friday.
Small craft criteria winds and waves won`t start until Friday
night, and continue into Saturday, mainly on Lake Michigan, and
portions of Lake Huron. The winds should diminish Saturday night.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

$$

NEAR TERM...JL
SHORT TERM...AS
LONG TERM...AS
AVIATION...JL
MARINE...JL